Fork springs

Front fork springs sacked out in 1200 miles. Overhaul length is down by 1/2 inch, but these springs are weak. They were new genuine springs. I need a recommendation for a good brand or maybe some heavy duty models. Riders weight is 200 pounds, Thanks, Dave

Simpliest way is clip off some snagged spring to shorten and stiffen it up some then sick in say valve springs for a progressive multi rate spring that can support your mass and braking inertia yet not jar the snot out of you or bike. Other wise best wishes as essentially everyone in you mass zone has complained of the off the self progress variety for many decades. Genuine English peope were too poor to get very heavy so need to look at foreign ones.

hobot said:

Genuine English peope were too poor to get very heavy so need to look at foreign ones.

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Thats made my day, Thanks Hobot. :lol:

Original stock Norton fork springs are wound very close coil,which means they ressist "getting shorter" i have compressed them untill coil bound on a screwed rod, they loose a 1/8 inch, but stablize there after,
I can only conclude your "genuine" ones are sub- standard.
14 stone os not heavy for the stock items, my MK3 was last owned by a big guy..28 stone! the forks are still almost full length.
Losing 1/2 in a short time suggests poor quality wire ,and heat treatment, after the spring is wound all quality springs are stress relieved . check out your next supplier!

I think progressive springs make a replacement for these?

hobot said:

Genuine English people were too poor to get very heavy so need to look at foreign ones.

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Best statement EVER! Just when I think you can't surprise us any more, you go and totally redeem yourself! Bravo sir.



As for the springs, external springs are also an option, they eliminate the coil bind, are lighter and look cool.

A famous Nortoneer Geoff something, had a batch of custom 3 rate stock lenght springs made that were a good bit stiffer in the high rate than the stock or other after market springs, so maybe we could convince a big spender vendor to order up another batch. Ms Peel lucked out on his last set. Otherwise why not combine inner and outer springs? Of course I think my mods and the kit sold by Greg Fualt put an end to Roadholder complaints.

Glad to entertain with hidden political social implications that ain't at all funny. Take Twiggy for instance or the term double crosser.

If the springs sagged 1/2",that won't change the spring rate.It will only change the ride height.
Were they ever any good,or was the spring rate too soft?You could put 1/2" spacers on the springs to restore the ride height.

You could put 1/2" spacers on the springs to restore the ride height.

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You then run the risk of the spring going coil bound before the compression bump stop starts to function, makes for an unpleasant ride.

Are progressive springs better or worse than oem? Wouldn't they initially provide less ground clearance since they would sag more under the same weight initially or do I have that all wrong? Would a set of oem original 1973 springs have noticeably lower ride height due to "wear" compared to a brand new set?

I guess I'm basically wondering if a new set of oem springs or a new set of progressive springs would give me a bit more ride height and any better shock action and, if both would do so, whether progressive would be overall better than non-progressive.

I can only speak about my xj 900 and progressive made a world of differeence on mine.

"I can only speak about my xj 900 and progressive made a world of differeence on mine."

In a GOOD way, right?

Could you give me an idea of what. specifically, was better by comparison?

I was not joking about the lighter weight of English men in general and therefore lighter general rates of springs supplied and the decades of consistent complaints of *any and all* after market springs that all behave rather softer to bottom way easier than plain red paint code Norton standard springs which IRRC is ~36.5 lb/inch. The improvements that others experience with foreign bike forks and progressive springs has no relation what so ever to what you can buy off the shelf currently form vendors of Norton progressive springs. Goggle the key words and see.

You then run the risk of the spring going coil bound before the compression bump stop starts to function, makes for an unpleasant ride.

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Beside the noise and clunk felt on coil bind it can also suddenly make bike perfer to straight steer on every little road lump like a scared bronco ya don't know which way its going to toss you off and slowing down don't help till able to put feel down. IRRC there's barely a 1/3" before Norton spring coil bind anyway.

Found this video which, though re KLR, not Commando, does seem to answer one question I had re progressives. In the video, it is demonstrated that the progressives have more resistance to initial sag which would seem, to me, to be advantageous for the type of riding I do. In the video, a stock KLR spring deflected 1.5" with a 50 lb load while a progressive deflected less than 1.25. Of course, I am ASSUMING that the same results would occur with a Commando oem spring vs a progressive and I don't really know that to be the case...

http://www.youtube.com/watch?v=b3fIc-8dt7U

"This video proves nothing .
It is just a VERY compicated way to determine a spring ratio ."

Seems to me to be the opposite, it demonstrates in the real world exactly what the spring does as far as sag as opposed to quoting some spring spec that means nothing to me. I agree that since it's for a KLR as opposed to a Commando, it does not mean the same thing happens with an oem Commando spring vs a progressive. Then again, I haven't heard an answer here from the commando community re that exact question - do the progressives sag more or less than oem? I'm not interested in spring rates; I want to know what the bike actually does with the two different springs.

I've seen plenty of posts re cutting springs/adding spacers/fork mods (I have the Fauth mod), etc but I am just trying to find out the answer to the question - do stock springs sag more than progressive springs. That video clearly answers it for a KLR...

The video was not surprising,
The issues here are what do you want from the forks?
Spring's simply hold the bike up , [for starters] then we require them to compress when under-taking differant road/track/field surface conditions, Also braking,riding two up, you are 200 lb and the wife is more,in a silly moment you deceide to go with hobit, leaping over rocks :lol:
Suddenly you are bottoming out ,crash bang!
Then next week you lend the bike to Jim ,hes 7 stone ,he thinks the forks are to firm!
Its impossible to please them all.
When Norton deceided to draw and produce a fork spring back in the 50's , what was the deceiding factor, 30 stone [Him and her,] or little Jim{ 95 lb ], off road,track touring?
It's just a compremise, bit like the the THREE bears MY springs to hard. mines to soft. mines...i think you get the picture.
But as dampers now play a great roll, some rebound and compression can control the forks {springs]
I have sold over 350 sets ,with only a hand full not happy. 20 race bike's are doing well, If Duncan {lansdowne manx] is over the moon [just ordered another set] then they must be making a differance. ...for Him!
Spoke to him last week, after a double win at oulton Park, His words " after a race the forks are just the same, nice and complient" ..bare in mind he's 7 stone,and the manx is as new. Thanks to Dave, he sets it up.


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I think there is a bit of confusion on discussing progressive rate springs vs just stronger over all spring rates. If you are heavy enough then just a stronger spring should prevent too much sag riding and drop on braking but will not give as pleasant a ride over rough stuff as over all rate is stiffer than stock. But the advantage of a proper configured progressive spring will be rather soft in the sag range for an inch or so that takes up/ignores normal road textures but then stiffen up dramatically towards end of travel w/o bottoming on pot holes and Armadillos. The KLM stiffer spring may well be about right for you, but only one way to really find out is spend and diddle them in and see.

Shade tree short cut would be keep the stock spring for the low rate soft early travel, stiffened up some by slicing out couple inches then stick in 2" stiffer spring, preferably progressive as a valve spring. Grind the end of cut spring coil more flat and put a washer between the springs. This will allow stock spring left overs to coil bind but still be supported by the stiffer section not bound up till reaching the short 4" limits of Commando issued Roadholder travel hitting roots, curbs or panic stops, if your brake and tire and panic intense enough.

Well, what I'm trying to do may be unattainable - I want to buy a set of springs that will sag less than the oem springs so as to maintain a decent ride height which is very important here in Mexico with all the speed bumps ("topes," in espanol), while, at the same time, providing more "absorption" of cobblestone/potholes, etc. I don't really want to do a lot of experimenting with different springs/cutting/spacers if I can avoid it. The bike also has to work in the twisties so I don't give up any ground to all the folks with their new(ish) dual sports. I'm 6ft, 165 lbs and there is never a passenger on the bike.

The stock springs are the originals from 1973. If I am careful going over the topes, the bike will USUALLY not strike the center stand/frame unless the tire pressure is less than 28/30psi. Tires are Avon Roadrunner 4.10/19s. I have never had the forks bottom out on any normal sort of bump/pothole/cobbles so IMO, it's not really a travel issue. That's why it SEEMS to me that a progressive spring might be helpful but I don't really want to buy a set just to find out that there is no improvement in what I need. But I may just go ahead and get a set of progressives when I'm in the US and if the work, they work and if they don't...well, I've thrown away 90 bucks on plenty of stuff that I didn't like!

Some 15 years ago I installed Progressive fork springs, for no reason other than I figured they just must be an improvement over the stockers.

I did not like them, they felt too stiff to me and I weigh 180.

Pulled them out and put back in the stock springs after a two year trial.

I have been reading about the high level or praise for John's fork kit and getting closer to placing an order!

John,

I didn't realize that you are the Landsdowne fork mod guy. Obviously I would think that adjustable compression/rebound would provide far more customization thatna fixed setup. I was quite pleased with the Fauth Fork mod compared with oem but your kit sounds like it might offer more of what I would like out of my forks. One thing I'm curious about is the fact that, if I read correctly, one fork does the compression damping while the other does rebound damping.

I would have thought that would provide an unbalanced feel to the front end as one fork would resist compression while the other wouldn't and the same with rebound. But apparently this doesn't actually occur (?) But doesn't that essentially cause the mechanism to wear out faster since the "work" is not spread out equally between the forks? I don't know the first thing about fork/damping design so I apologize if my questions/supposition is stupid.